On July 10, 2007, it was reported that Liverpool F.C. had made a £13.5 million offer to the Amsterdam club. On July 12, it was reported that Liverpool and Ajax agreed a fee in the region of £11.5 million, and later Liverpool confirmed that Babel would sign a five year contract on July 13. He was unveiled on July 13 with Yossi Benayoun. Babel was handed the number 19 shirt. He made his debut on July 17 against Werder Bremen in a friendly. He was due to play in the first round of the Barclays Asia Trophy 2007 but for a delay in the granting of international clearance. This was sorted out in time for the final against Portsmouth.

He made his Premiership debut in the 2007/08 Premiership curtain raiser against Aston Villa away after coming on off the bench, impressing by going close twice and showing great vision and touch. A week later and he made his Anfield debut, coming off the bench against Chelsea and producing a cross and a shot that went wide. Babel plays in the right or left midfielder position, or as a centre forward for Liverpool. On September 1, Babel scored his first goal for Liverpool against Derby County. He cleverly dummied the ball aside from the two oncoming sliding defenders, before sending Stephen Bywater, Derby's goalkeeper, to the wrong corner and scored. Babel scored his first two goals for Liverpool in the Champions League on November 6, 2007 against Beşiktaş J.K. after coming on as a substitute. He nearly got a third, to complete a hat-trick, off a header from a Harry Kewell cross but was denied by the crossbar. Liverpool and Celtic legend Kenny Dalglish has said that Babel has the ability to terrorise defenders in the Premier League with his pace and trickery with the ball. Babel scored the fourth and last goal in Liverpool's vital UEFA Champions League 2007-08 group stage campaign match against Olympique de Marseille, which they needed to win. Since then Ryan Babel has scored 3 more goals for the 1st team bringing his tally up to 7 goals in 19 appearances.